This invention relates to a method and an apparatus for reducing flare smoke emissions discharged to the atmosphere. In another aspect the invention relates to refinery relief systems in which a flare system is used. In still another aspect this invention relates to the proper operation of a flare system to protect the environment while being used to eliminate combustible waste gases.
It is common practice for refineries to collect combustible waste gas and to pass it to a flare system for burning. Refineries built to process combustible gases are constructed so that vessels used in the refining process are designed to withstand normal pressure variations during routine plant operations. However, to prevent the rupture of these vessels when operating conditions would result in pressures that exceed their design pressure limits, safety relief valves are placed on these vessels to vent the gases. These vented gases are passed to a flare system where the combustible gases are burned. A properly operated flare system protects the environment such as by eliminating the production of smoke while being used to safely and economically eliminate combustible waste gases.
While it is within the capability of one skilled in the art to design a flare that will burn combustible gases without producing appreciable amounts of smoke, such designs generally require that the amount and composition of the waste gases be reasonably constant, a requirement which is usually not practicable. In order to overcome the production of smoke when flaring combustible gases one rather common technique is to pass steam to the flare along with the combustible gases, however, this technique does not completely solve the smoke problem.
It is therefore an object of this invention to provide a method and an apparatus for the reduction of flare smoke emissions discharged to the atmosphere during the burning of combustible gases. Another object of this invention is to provide a method and an apparatus for the reduction of flare smoke emissions when steam is passed to the flare along with the combustible gases.
Other objects and advantages of the invention will be apparent from the foregoing brief description of the invention and the appended claims as well as from the detailed description of the invention as described herein.